The surface integrity and notched fatigue property of a shot-peened single crystal superalloy were investigated. The surface texture of the peened material was determined using a white light interferometer, while the microstructural characterization was performed using a scan electron microscopy, high resolution transmission electron microscopy from the plane and cross-section view directions, micro-hardness tester and electron backscatter diffraction. The gains, expressed in term of high temperature fatigue limit, were established by rotating-bending fatigue tests and discussed in relation to the microstructure evolution in the shot peening states. This revealed that the beneficial effect provided by shot peening is more than 14.8% against as-machined in a temperature ranging from 760℃ to 850℃ because of the high-density tangled dislocation, cold work and disorientation. Furthermore, the stress concentration coefficient is reduced by the shot peening procedure while the average profile height Ra increases according to the calculation of the surface stress concentration.